The orbital portion of the lacrimal gland is located in the superotemporal orbit and the palpebral portion of the lacrimal gland is located on the posterior surface of the superotemporal upper lid. The lacrimal gland produces the aqueous portion of the tear film. Ductules from the orbital portion of the lacrimal gland pass through the adjacent palpebral lacrimal gland to empty in the superior conjunctival cul-de-sac. Smaller accessory lacrimal glands in the upper and lower lids also contribute to tear production. The tears bathe the surface of the eye and then drain into the puncta and canaliculi in the medial upper and lower lids. The superior and inferior canaliculi join as the short common canaliculus. The tears flow from the superior and inferior canaliculi through the common canaliculus, into the lacrimal sac, and down the nasal lacrimal duct into the nose.
The canaliculi can become obstructed or stenotic on a congenital basis or from trauma such as lacerations, from inflammation, from certain types of chemotherapy, such as taxotere or five-fluorouracil—which may also affect the nasolacrimal duct—or the obstruction can be idiopathic. When the upper and lower canaliculi or the common canaliculus become obstructed, tears can no longer drain from the surface of the eye through the lacrimal system into the nose. The tears well up in the eye as a result, and run down the face. The excess tears blur the vision and the patient has to constantly dab the eye.
The nasolacrimal duct can also become obstructed and, as a result, damaged as a result of a congenital obstruction or an acquired obstruction. Tears stagnating in the lacrimal sac and bacteria multiplying therein lead to an infection of the lacrimal sac in many patients suffering from nasolacrimal duct obstruction. The result is a painful enlargement of the lacrimal sac swollen with pus, and a discharge over the eye.
Canalicular obstruction or stenosis is usually treated by forming a new passage through the obstruction with a probe, also by dilatation with probes or with a balloon catheter. At times, a dacryocystorhinostomy (DCR) is performed. A DCR consists of the surgical creation of a new passageway from the lacrimal sac into the nasal cavity. This can be performed with a balloon catheter using an endoscope or externally through an incision. A silicon tube is most often placed in the lacrimal system whether or not a DCR is performed.
In the case of trauma to the lacrimal drainage system, an intubation is performed to prevent scars from permanently clogging the canaliculi or nasolacrimal duct. In cases of canalicular or nasolacrimal duct obstruction from chemotherapy, intubation is performed as quickly as possible to prevent complete, irreversible closure.
Congenital nasolacrimal duct obstruction is treated with probing or through balloon catheter dilatation. However, intubation is also needed in some resistant cases.
Accordingly, intubation of the lacrimal system preferably with a silicon tube, is often performed after lacrimal surgery or as a primary treatment for nasolacrimal duct obstruction, canalicular stenosis, or canalicular laceration. The easiest device to insert is the Mini-monoka tube that consists of a silicon tube attached to a punctal plug. The tube is inserted through one canaliculus into the lacrimal sac. The plug on the proximal end of the tube is positioned at the punctum. The tube will thus stay in place without having to enter the nasolacrimal duct or the nose. Indeed, the Mini-monoka tube cannot generally be placed in the nasolacrimal duct or nose. If, however, intubation of the nasolacrimal duct is needed, then one of the two ends of the silicon tube is threaded through the canaliculus and down the nasolacrimal duct into the nose. The distal end of the tube, or of any probe attached to it, must be grasped in the nose and pulled into position. It can be very difficult to locate and grasp the tube in the nose of some patients. In some cases, it is impossible to find the tube. That is because the nasolacrimal duct empties into the nasal cavity in the inferior meatus beneath the inferior turbinate. U.S. Pat. No. 6,383,192 discloses a way to push an intubation device by means of a rod. However this method still require pulling the device out of the lacrimal duct from inside the nasal cavity. The nasolacrimal duct is very hard or impossible to visualize even with the help of a flexible endoscope. It is also very difficult to locate the duct simply by tactile sensation with an instrument. U.S. Pat. No. 6,878,165 Makino teaches another verification method involving the insertion of a miniature light at the tip of a probe or stent. The illumination of the nasal cavity offers visual proof that penetration is complete, unless, as is usually the case, the light is blocked by an edema or an accumulation of blood.
Obstruction of the nasolacrimal duct occurs in 2 percent to 6 percent of newborns. Congenital nasolacrimal duct obstruction usually resolves with the use of antibiotic drops and massage of the lacrimal sac. However, a significant number of patients require surgical treatment for congenital nasolacrimal duct obstruction. A probing is usually performed in these children. If silicone intubation needs to be performed, then the location and course of the nasolacrimal duct may need to be confirmed by probing before performing intubation of the lacrimal system.
Probing is performed by inserting a probe horizontally through the punctum and canaliculus into the lacrimal sac. The probe is then oriented vertically and pushed down the nasolacrimal duct into the nasal cavity. The surgeon must then confirm that the probe has penetrated all obstructions in the nasolacrimal duct and reached the nasal cavity. This is commonly done by placing a metal instrument into the nose and touching the probe. The surgeon feels for metal on metal contact indicating that the probe has entered the nasal cavity.
The probe is then removed from the lacrimal system. A syringe filled with fluorescein stained water with an attached short cannula is placed in the canaliculus and the fluid is irrigated through the lacrimal system into the nose. The fluid is recovered in the nose with a suction catheter. This confirms that the lacrimal system is patent after the probing. If the fluid does not irrigate into the nose, then the probing is repeated.
Probing presents several problems. The probe enters the nasal cavity through the opening of the nasolacrimal duct in the lateral nasal wall beneath the inferior turbinate. This area is difficult to access, making it often impossible for the surgeon to touch the probe in the nose with another instrument. In this event, the surgeon cannot confirm if the probe has entered the nasal cavity. Another problem is that irrigation of the lacrimal system is required to determine if the nasolacrimal duct obstructions have been opened. If irrigation through the lacrimal system down to the nasal cavity is not verified, the probing must be repeated. As a result, multiple procedures are performed that can cause repeated trauma to the lacrimal drainage system with each placement of a probe or cannula.
Bleeding in the lacrimal system or nose often occurs during the probing, intubation or associated procedures. The applicant is not aware of any expedient and practical device for clearing blood from the lacrimal system. Furthermore, the only known method for removing blood from the nasal cavity is by introducing into the nose a suction catheter through the naris. It is often difficult if not impossible to position the catheter in the inferior meatus in order to remove blood around the nose end entry into the nasolacrimal duct.
The probes of the prior art are solid metal rods made of steel, bronze, silver or other metal. A flattened area in the center of the probe facilitates its manipulation.
The instant invention results from attempts to achieve intubation without having to retrieve the end of the tube inside the nose, to perform probing and irrigation in a single step, to expediously clear blood and other fluids from the nasal cavity and the nasolacrimal duct.